Biological, psychological, and social factors all play a role to varying degrees in causing depression. depression results when a preexisting
vulnerability, or diathesis, is activated by stressful life events.The preexisting vulnerability can be either genetic, implying an interaction between nature and nurture, or the result of past experience such as learned views of the world formed in childhood. The heritability (the degree to which individual differences in occurrence are associated with genetic differences) of depression is to be approximately 40% for women and 30% for men.
Biological Causes: imbalance in neurotransmitter
Most mood disorders result from an imbalance in some of the neurotransmitter systems of the brain. Neurotransmitters are protein substances that neurons use to communicate with each other. There are many kinds of neurotransmitters: acetylcholine, glutamate, norepinephrine, serotonin, and dopamine. Norepinephrine, serotonin, and dopamine are in the minority. Only a small fraction of the brain's neurons use these neuro-transmitters to signal other cells. However, since these three neurotransmitters are very powrful, they can modulate the activity of the entire brain. Mood disorders have been linked primarily to a dysfunction in the norepinephrine and serotonin. In other cases, hormones such as steroid or thyroid play a role in developing mood disorders. Genetics also plays a key role in the development of mood disorders, especially bipolar disorder.
Psychological Causes: emotional and physical state
Various aspects of personality and its development appear to affect the occurrence of depression. Although depression is strongly related with adverse events, a person's style of dealing with the daily events may be correlated with their flexibility.
It is not perfectly clear which factors cause depression and what the effects are. However, depressed people who are able to correct their thinking patterns often show improved mood and self-esteem. Low self-esteem and self-defeating or distorted thinking are related to depression. Also, Depressed people often criticize themselves for negative events. They feel responsible for negative events but did not take credit for positive outcomes.
- negative belief about oneself
- obsession on experience of failure
- observing the failure of social models
- lack of social persuasion on success
- inactive physical and emotional states
- tension and stress
Social Causes: stress and social support
Poverty and social isolation are associated with increased risk of psychiatric problems in general. For example, child abuse is also associated with increased risk of depressive disorders later in life. Disturbances in family functioning, such as parental depression, severe martial conflict or divorce, death of a parent, or other disturbances in parenting are additional risk factors.
In adulthood, stressful life events are strongly associated with the onset of major depressive epidsodes. A first episode is more likely to be preceded by stressful life events than are recurrent ones. The relationship between stressful life events and social support has been a subject of debate. The lack of social support may enhance the possibility that stress will lead to depression, or the absence of social support may form a strain that leads to depression directly. There is evidence that neighborhood social disorder, for example, due to crime or illicit drugs, is a risk factor, and that a high neighborhood socioeconomic status, with better amenities, is a protective factor. Adverse conditions at work, particularly demanding jobs with little scope for decision-making, are associated with depression, although diversity and confounding factors make it difficult to confirm that the relationship is casual.
Final Analysis: Depression results from a combination of causes!
As shown above, depression or mood disorder stem from a hundreds of causes: biological, psychological, social, etc. Since there are several possibilities of any cause behind the mood disorder, it is unclear which cause is directly associated to depression. Also, the cause depends on person; for example, some people might have mood disorder because they inherited it. Other people would suffer from the disorder due to the stressful life or psychological problems.
Causes of Depression
Video Clip: Dr. Matthew describes how neurotransmitter affects depression. (0:31)
http://overcoming-depression.org/files/2007/04/depression-progression.jpg
Causes of mood disorders
Biological, psychological, and social factors all play a role to varying degrees in causing depression. depression results when a preexistingvulnerability, or diathesis, is activated by stressful life events.The preexisting vulnerability can be either genetic, implying an interaction between nature and nurture, or the result of past experience such as learned views of the world formed in childhood. The heritability (the degree to which individual differences in occurrence are associated with genetic differences) of depression is to be approximately 40% for women and 30% for men.
Biological Causes: imbalance in neurotransmitter
Most mood disorders result from an imbalance in some of the neurotransmitter systems of the brain. Neurotransmitters are protein substances that neurons use to communicate with each other. There are many kinds of neurotransmitters: acetylcholine, glutamate, norepinephrine, serotonin, and dopamine. Norepinephrine, serotonin, and dopamine are in the minority. Only a small fraction of the brain's neurons use these neuro-transmitters to signal other cells. However, since these three neurotransmitters are very powrful, they can modulate the activity of the entire brain. Mood disorders have been linked primarily to a dysfunction in the norepinephrine and serotonin. In other cases, hormones such as steroid or thyroid play a role in developing mood disorders. Genetics also plays a key role in the development of mood disorders, especially bipolar disorder.Psychological Causes: emotional and physical state
Various aspects of personality and its development appear to affect the occurrence of depression. Although depression is strongly related with adverse events, a person's style of dealing with the daily events may be correlated with their flexibility.It is not perfectly clear which factors cause depression and what the effects are. However, depressed people who are able to correct their thinking patterns often show improved mood and self-esteem. Low self-esteem and self-defeating or distorted thinking are related to depression. Also, Depressed people often criticize themselves for negative events. They feel responsible for negative events but did not take credit for positive outcomes.
To summarize, the psychological causes for depression are:
- negative belief about oneself
- obsession on experience of failure
- observing the failure of social models
- lack of social persuasion on success
- inactive physical and emotional states
- tension and stress
Social Causes: stress and social support
Poverty and social isolation are associated with increased risk of psychiatric problems in general. For example, child abuse is also associated with increased risk of depressive disorders later in life. Disturbances in family functioning, such as parental depression, severe martial conflict or divorce, death of a parent, or other disturbances in parenting are additional risk factors.
In adulthood, stressful life events are strongly associated with the onset of major depressive epidsodes. A first episode is more likely to be preceded by stressful life events than are recurrent ones. The relationship between stressful life events and social support has been a subject of debate. The lack of social support may enhance the possibility that stress will lead to depression, or the absence of social support may form a strain that leads to depression directly. There is evidence that neighborhood social disorder, for example, due to crime or illicit drugs, is a risk factor, and that a high neighborhood socioeconomic status, with better amenities, is a protective factor. Adverse conditions at work, particularly demanding jobs with little scope for decision-making, are associated with depression, although diversity and confounding factors make it difficult to confirm that the relationship is casual.Final Analysis: Depression results from a combination of causes!
As shown above, depression or mood disorder stem from a hundreds of causes: biological, psychological, social, etc. Since there are several possibilities of any cause behind the mood disorder, it is unclear which cause is directly associated to depression. Also, the cause depends on person; for example, some people might have mood disorder because they inherited it. Other people would suffer from the disorder due to the stressful life or psychological problems.Home
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